A chat with Tom Hanks is like a box of chocolates … you never know what you’re gonna get!

The perennial A-lister said the F-word on Good Morning America‘s live broadcast Friday, shocking the in-studio crowd, who were mortified to hear the show biz vet break a cardinal broadcasting rule.

Speaking with host Elizabeth Vargas, the Sleepless in Seattle star was asked to do some dialogue with one of the 75 affectations he uses in his new flim, Cloud Atlas. The Castaway star obliged, doing the schtick before the F-word inadvertently slipped out.

“I’m sorry, I slipped into a brand of acting,” Hanks said. “I have never done that before. I want to apologize to the kids in America that are watching this right now.”

Hanks joked that the next time he appears on the show, he’s sure there will be a 7-second delay as a safeguard to his potty mouth.